ATC told to avoid dense populations when re-routeing

UK regulators are advising air traffic controllers to avoid re-routeing aircraft over densely populated areas during emergencies if there is reason to doubt the aircraft can maintain controlled flight.

The amended policy follows an incident two years ago in which an Evergreen International Boeing 747-100 suffered engine failure and was diverted over central London in order to land at the city’s Heathrow airport.

During the April 2004 event the crew had expressed concern about the aircraft’s other engines. UK investigators said that, although the aircraft landed safely, the incident raised questions as to whether the jet should have been allowed to fly over a congested city.

UK Civil Aviation Authority safety regulators have since reviewed and updated the policy for handling such emergencies.

In an amendment to air traffic services procedures, which takes effect from 28 April, the CAA states: “It is desirable that aircraft in emergency should not be routed over densely populated areas, particularly if there is reason to believe that the aircraft’s ability to remain in controlled flight is compromised or that parts of the aircraft could detach in flight.”

While not referring specifically to the Evergreen incident, the CAA says that the updated policy is “necessary” to resolve recently identified safety concerns.

It maintains, however, that controllers must weigh the risks to those on the ground against the possible risks to a crippled aircraft that might arise should it be kept airborne longer than necessary.

“If [re-routeing away from congested areas] is inconsistent with providing the most appropriate service to the aircraft – for example, when any extended routeing could further jeopardise the safety of the aircraft – the most expeditious route is the one that should be given.”


Source: Flight International